I was wondering what the experts think about using UV filters. I have one mainly to protect the front lens, but i wonder if the filter deteriorates the image??

You can find threads on DPR and web pages describing issues related to this. It seems that lights can cause additional flare with the added glass, but as the others said, the coatings on the filter can make a difference. Even so, I decided a long time ago to not bother with a UV filter and try to use a hood for extra protection. I figure I take my chances, and if something happens, it happens. Then again, I don't have really expensive lenses. By the way, to get over obsessiveness about having a perfect front element, see some of the comparisons where people purposefully damaged it, and you can hardly tell in the results. I worry less about specks of dust on the front element.